This bit sounds terrible --
Buying or selling a vehicle
When buying a used vehicle you will be able to use the V5C/2 - new keeper supplement to pay vehicle tax at a Post Office branch, along with the MOT certificate (if applicable) and fee. From 1 October 2014 you will also be able to pay vehicle tax using the V5C/2 online or by phone.
When selling a vehicle to a new vehicle keeper, the vehicle tax will no longer be transferable. Vehicle tax will end when a vehicle is sold and the new keeper will need to get the vehicle taxed immediately before the vehicle can be used.
How much messing about and having to fork out extra cash for the tax when buying a vehicle ... it was always good to buy a vehicle that had tax on it -- plus more money for the government AGAIN